1. Field of the Invention
The present invention relates, in general, to agricultural sweeps and, more specifically, to an improved agricultural sweep and an improved method of manufacturing an agricultural sweep.
2. Information Disclosure Statement
Agricultural sweeps are generally pulled by agricultural tractors or the like. Such sweeps are generally used to till the ground by cutting off or uprooting undesirable plants, breaking up the soil, etc. A typical agricultural sweep includes an earth or ground engaging body portion and a stem portion extending upward from the body portion for being attached to a tractor or the like. The ground engaging portion typically has a forward nose or point and one or two swept back wing portions extending back from the forward nose. A cutting edge generally extends from the leading edge of the nose along the leading edge of each wing portion.
Since such tillage tools are commonly pulled through the soil by tractors at relative high forward velocities, they are subjected to substantial wear and tear. Adams Hardfacing of Guyman, Okla. is believed to have pioneered the use of hard-facing the cutting edge of tillage tools in the 1920's as a means of keeping the cutting edge sharp, which, in turn, makes it easier for the tools to be pulled through the ground. Hardfacing is the process of welding an abrasion and wear resistant metal onto parts or surfaces subjected to rapid wear. As agricultural tractors became more powerful, hard-facing also became a means of enhancing the expected useful life of tillage tools.
Another well-know process of hard surfacing the cutting edge of tillage tools includes applying heat with an oxygen acetylene torch to the cutting edge and then fusing a hard face rod to the base metal. This very high and uneven heat that is applied to the base metal in this process is conductive to causing microscopic heat fractures to develop in the base metal. It is believed that Sam Alessi invented a process, now commonly know as the "Dura-Face" process, in the mid-60's while an employee of the Ingersoll Products Division of Borg Warner Corp., in which a metal alloy compound is applied to a part before heating, not simultaneously as in the hard-facing process. After the metal alloy compound is applied, the entire part is heated to a temperature in excess of 2,100.degree. Fahrenheit. At that point, the metal alloy compound is impregnated into the base metal. The critical high-heating process is conducted in an atmospherically controlled environment to avoid decarbonization of the base metal, which could prevent the metal alloy compound from being impregnated into the base metal. The basic "Dura-Face" process and composition is disclosed in Alessi, U.S. Pat. Re. 27,851, reissued Dec. 25, 1973.
Another concept for increasing the useful life of the cutting edge of agricultural sweeps is based on designing the sweep to permit uniform wear across the face of the sweep without narrowing the overall width of the sweep or blunting its point as taught by Nichols, U.S. Pat. No. 4,787,462, issued Nov. 29, 1988. Nichols discloses an earth cultivating sweep including an elongated body 12 terminating in a front nose portion 14. A stem 16 is provided for attaching the body 12 to the implement. A pair of laterally extending wing members 20, 22 diverge rearwardly from the body 12. Each wing member 20, 22 defines a continuous front cutting surface 32, 34 along its forward edge between the nose 14 and the distal tip portions thereof. Each cutting surface 32, 34 is shaped in a concave curve between the nose 14 and distal tip portions. Each wing member 20, 22 further defines a continuously concave bottom surface 46, 48 which extends between the front cutting surface 32, 34 and the rear edge of each wing member 20, 22.
While the above processes and designs have been effective in maintaining the sharpness and life of the cutting edge of tillage tools, as tractors became more powerful, more stress was applied to the tillage tools, resulting in failure of the tillage tools at areas other that the cutting edge. With agricultural sweeps, failure often occurs at the stem or shaft joining the ground engaging portion to the tractor, etc. Johnson, U.S. Pat. No. 4,580,639, issued Apr. 8, 1986, discloses an agricultural sweep having an elongated protrusion on the upper surface of the ground engaging portion extending from the forward point or nose thereof to the base of the stem or shaft thereof for deflecting soil around the shaft or stem and for reducing any soil build-up in front of the shaft or stem, thereby reducing the drag created by the sweep, etc. The Johnson sweep includes a shaft 8 for being attached to the tine of the agricultural machine, and an earth engaging portion 9 which comprises an inclined point 10, steeply inclined side faces 11, and an elongated protrusion 14 extending from the point 10 toward the base of the shaft 8. The protrusion 14 is formed by indentation of the undersurface of the earth engaging portion 9 and is intended to provide a flow of soil over the sweep without any build up in front of the shaft 8.
Nothing in the known prior art discloses or suggests the present invention. More specifically, nothing in the known prior art discloses or suggests an agricultural sweep for being attached to a tractor that pulls the agricultural sweep across the ground, the agricultural sweep including a ground engaging portion having a cutting edge for cutting through the ground as the sweep is pulled across the ground; a stem portion for attaching the ground engaging portion to a tractor; and an extended wear portion applied to the stem portion for rendering the stem portion resistant to abrasion.